原标题：NXP LPC81xM 32位ARM Cortex-M0+ MCU开发方案

　　nxp公司的LPC81xM系列产品是基于ARM Cortex-M0+内核的低成本32位MCU,CPU工作频率高达30MHz,支持高达16KB闪存和4KB SRAM,外设包括CRC引擎,I2C总线接口,多达三个UART,多达两个SPI接口,一个多速率定时器,自叫醒定时器和状态可配置的定时器,一个比较器,功能可配置的I/O端口和多达18个通用I/O引脚,主要用于照明, 消费类电子,马达控制,火警和安防和气候控制.本文介绍了LPCXpresso812 MAX主要特性和优势,框图, 评估板LPCXpresso812-MAX主要特性和电路图.

　　The LPC81xM are an ARM Cortex-M0+ based, low-cost 32-bit MCU family operating at CPU frequencies of up to 30 MHz. The LPC81xM support up to 16 kB of flash memory and 4 kB of SRAM.

　　The peripheral complement of the LPC81xM includes a CRC engine, one I2C-bus interface, up to three USARTs, up to two SPI interfaces, one multi-rate timer, self wake-up timer, and state-configurable timer, one comparator, function-configurable I/O ports through a switch matrix, an input pattern match engine, and up to 18 general-purpose I/O pins.

　　LPCXpresso812 MAX主要特性和优势:

　　 System:

　　 ARM Cortex-M0+ processor, running at frequencies of up to 30 MHz with single-cycle multiplier and fast single-cycle I/O port.

　　 ARM Cortex-M0+ built-in Nested Vectored Interrupt Controller (NVIC).

　　 System tick timer.

　　 Serial Wire Debug (SWD) and JTAG boundary scan modes supported.

　　 Micro Trace Buffer (MTB) supported.

　　 Memory:

　　 Up to 16 kB on-chip flash programming memory with 64 Byte page write and erase.

　　 Up to 4 kB SRAM.

　　 ROM API support:

　　 Boot loader.

　　 USART drivers.

　　 I2C drivers.

　　 Power profiles.

　　 Flash In-Application Programming (IAP) and In-System Programming (ISP).

　　 Digital peripherals:

　　 High-speed GPIO interface connected to the ARM Cortex-M0+ IO bus with up to 18 General-Purpose I/O (GPIO) pins with configurable pull-up/pull-down resistors, programmable open-drain mode, input inverter, and glitch filter.

　　 High-current source output driver (20 mA) on four pins.

　　 High-current sink driver (20 mA) on two true open-drain pins.

　　 GPIO interrupt generation capability with boolean pattern-matching feature on eight GPIO inputs.

　　 Switch matrix for flexible configuration of each I/O pin function.

　　 State Configurable Timer/PWM (SCTimer/PWM) with input and output functions (including capture and match) assigned to pins through the switch matrix.

　　 Multiple-channel multi-rate timer (MRT) for repetitive interrupt generation at up to four programmable, fixed rates.

　　 Self Wake-up Timer (WKT) clocked from either the IRC or a low-power, low-frequency internal oscillator.

　　 CRC engine.

　　 Windowed Watchdog timer (WWDT).

　　 Analog peripherals:

　　 Comparator with internal and external voltage references with pin functions assigned or enabled through the switch matrix.

　　 Serial interfaces:

　　 Three USART interfaces with pin functions assigned through the switch matrix.

　　 Two SPI controllers with pin functions assigned through the switch matrix.

　　 One I2C-bus interface with pin functions assigned through the switch matrix.

　　 Clock generation:

　　 12 MHz internal RC oscillator trimmed to 1.5 % accuracy that can optionally be used as a system clock.

　　 Crystal oscillator with an operating range of 1 MHz to 25 MHz.

　　 Programmable watchdog oscillator with a frequency range of 9.4 kHz to 2.3 MHz.

　　 10 kHz low-power oscillator for the WKT.

　　 PLL allows CPU operation up to the maximum CPU rate without the need for a high-frequency crystal. May be run from the system oscillator, the external clock input CLKIN, or the internal RC oscillator.

　　 Clock output function with divider that can reflect the crystal oscillator, the main clock, the IRC, or the watchdog oscillator.

　　 Power control:

　　 Integrated PMU (Power Management Unit) to minimize power consumption.

　　Reduced power modes: Sleep mode, Deep-sleep mode, Power-down mode, and Deep power-down mode.

　　Wake-up from Deep-sleep and Power-down modes on activity on USART, SPI, and I2C peripherals.

　　 Timer-controlled self wake-up from Deep power-down mode.

　　 Power-On Reset (POR).

　　 Brownout detect.

　　 Unique device serial number for identification.

　　 Single power supply.

　　 Operating temperature range -40 ℃ to 105 ℃ except for the DIP8 package, which is available for a temperature range of -40 ℃ to 85 ℃.

　　 Available as DIP8, TSSOP16, SO20, TSSOP20, and XSON16 package

　　LPCXpresso812 MAX应用:

　　 8/16-bit applications

　　 Lighting

　　 Consumer

　　 Motor control

　　 Climate control

　　 Fire and security applications

　　图1. LPCXpresso812 MAX框图

　　评估板LPCXpresso812-MAX

　　The LPCXpresso812-MAX board with NXP’s LPC812 Cortex-M0+ microcontroller is designed to make it as easy as possible to get started with your project.

　　LPCXpresso™ is a low-cost development platform available from NXP, supporting NXP’s ARM-based microcontrollers. The platform is comprised of a simplified Eclipse-based IDE and low-cost target boards which include an attached JTAG debugger. LPCXpresso is an end-to-end solution enabling embedded engineers to develop their applications from initial evaluation to final production.

　　评估板LPCXpresso812-MAX主要特性:

　　Fully supported by LPCXpresso Eclipse-based IDE and GNU C/C++ toolchain, available in free and Pro versions

　　Works with by Keil, IAR and other toolchains with CMSIS-DAP support

　　Integrated JTAG Debugger which can also be used to debug external target

　　LPCXpresso / mbed and Arduino UNO expansion connectors give simple access to a wide range of available expansion boards

　　Embedded Artists 14-pin expansion connector

　　Tri-color LED

　　On-board ADC

　　Reset and User interrupt buttons for easy testing of software functionality

　　The LPCXpresso-MAX family of boards provide a powerful and flexible development system for some of NXP’s low end MCUs. They can be used out of the box with a range of development tools, including the LPCXpresso IDE, as well as with ARM’s mbed online toolchain.

　　The standard LPCXpresso-MAX board design offers the following features:

　　Built in CMSIS-DAP based debug probe, based on the NXP LPC11U3x MCU.

　　Compatible with LPCXpresso IDE, mbed and other toolchains

　　Debug connector to allow debug of target MCU via an external probe.

　　Tri-color LED

　　Target ISP and WAKE buttons (LPCXpresso824-MAX)/User interrupt button

　　(LPCXpresso812-MAX)

　　Target Reset button

　　Expansion options:

　　MCU pins available on ‘standard LPCXpresso/mbed’ expansion connector (board bottom side)

　　Arduino connectors compatible with the ”Arduino UNO” platform (board top side)

　　Other expansion options (see board specific information below)

　　Powered from multiple sources

　　Link2 (debug probe) USB

　　LPCXpresso/mbed header

　　Options to allow measurement of current consumed by target MCU

　　图2. 评估板LPCXpresso812-MAX外形图

　　图3. 评估板LPCXpresso812-MAX电路图(1)

　　图4. 评估板LPCXpresso812-MAX电路图(2)

　　图5. 评估板LPCXpresso812-MAX电路图(3)